Process for the manufacture of compressed yeast



Patented Mar. 20, 1923.

UNITED STATES,

1,449,104 PATENT omce.

FRIEDRICH HLYDU CK, OF WILMEBSDOBF, GERMANY, ABBIGNOB TO THE FLEIBCH-HANN COMPANY, OF NEW YORK, N. Y., A CORPORATION OF OHIO.

PROCESS FOR THE MANUFACTURE OF COMPRESSED YEAST.

No Drawing.

To all whom it may concem:

Be it known that I, FRIEDRICH HAYDUCK, a citizen of Germany, residin atWilmersdorf, Germany, have invente certain new and useful Improvementsin Processes for the Manufacture of Compressed Yeast (for which patentapplication was filed in Germany August 19, 1915, Patent No. 303,252),of which the following is a specification.

This invention relates to a process of manufacturing yeast and moreparticularly to the process described in m copending United Statesapplication, Serial No. 420.- 829, which corresponds to German PatentNo. 300,663, in which a process for the manufacture of a compressedbakers yeast from a solution of sugar material and inorganic yeastnutrient salts is disclosed, of a character which is commerciallypractical and has for its object a process of propagating yeast innutrient solutions which are devoid of potassium, sodium being presentin lieu thereof.

In the manufacture of yeast it has generally been assumed that theelement potassium. which is an essential component of every plant, couldnot be dispensed with or replaced by any other substance. I haveascertained, however, that potassium as a component of yeast can beentirely replaced by sodium.

According to the process described in my co-pending United Statesapplication, Serial No. 420,829, yeast is propagated with aeration in adilute nutrient solution which contains sugar material and relativelylarge amounts of inorganic nutrient salts comprising, ammoniumphosphate, ammonium sulphate, calcium sulphate, magnesium sulphate andpotassium sulphate.

In practicing the process of the present invention a similar rocedureand nutrient solution is employed except that the potassium salt isreplaced by a similar salt of sodium. The sodium salts which it isreferable thus to employ are: sodium sulp ate,

mono-basic and (ii-basic sodium phosphate and sodium carbonate.

The ashes of compressed yeast, which has been grown for many generationsin accordance withthe process of this invention in nutrient solutionscontaining no potassium salts but only sodium salts, show, as the resultof my analyses, that sodium ocours in them in those quantities which areApplication filed October 30, 1920. Serial 1T0. 420,831.

Pure compressed yeast grown by this process, which was free from moldyyeast,

was selected for test purposes.

The nutrient solution adapted for yeast propa tion by this process wouldhave, for examp e; the following composition:

100 parts raw sugar, first product;

4.5 parts (N H,) SO ammonium sulphate;

1.5 parts (NHJH PO ammonium dihydrogen-phosphate 6.8 parts NaSO,+10H,O(=3g.Na SO,) sodium sulphate;

' 0.5 parts MgSO, magnesium sulphate;

5000 parts water.

To the above solution seven parts of chalk are added for the purpose ofneutralizing the mineral acids set free by the yeast during propagation.

In individual tests, the yeast was grown in nutrient solutionscontaining instead of raw su ar, purified raw sugar or raflinade(refined sugar). Also, instead of sodium sulphate, equivalent quantitiesof other sodium salts, as mentioned above, were substituted. The firstpreparation contained 20 parts of pure yeast, type M, which is a wellknown variety of yeast, and is described in bulletins which arefrequently published by the Laboratorium des Institute fiirGarungsgewerbe in Berlin. Air was blown through the nutrient solutionthus prepared, in the manner customarily practiced in the aerated yeastprocess, for a period of about 10 to 15 hours. The temperature wasmaintained between the limitsof 25 to 30 C.

The amount of yeast obtained on theaverage from seven experiments inwhich the yeast was propa ated seven times in nutrient solutions devoiof potassium compounds was as follows: 64% of the weight of the totalsugar material employed or 44% of the sugar material calculated afterdeducting the seed yeast which was 20% of the sugar material used. Afterthe. yeast had been propagated through five times it contained arelatively lar amount of sodium and a relatively smal amount ofpotassium, the ash thereof containing 18.2% sodium (Na),

at potassium itpropagated through five times it contained a relativelylar e amount of sodium and a relatively smal amount of potassium, theash thereof containing 18.2% sodium (Na), 4.7% potassium (K) as against28% potassium, which is the usual potassium content of the ash ofnormally nourished yeast.

When alterin the process so as to effect the gradual a dition of thenutrient solution to the fermenter and the amount of seed yeast employedincreased to 25 parts, the yield of yeast can be still furtherincreased. The amount of yield, resulting from this change, whencomputed on the basis of the sugar content orginally present was: 110percent, or 85 percent after deducing the seed yeast. The yeast wasobtained in the usual compressed form.

Yeast obtained by this process, as is sometimes the case with commercialbakers yeast, will at times contain a little mold. The

mold content is only a very slight percenti lhe raising force (bakingegualities) in all sodium yeasts correspond to that of cod baking yeast,used for baking purposes. n regard to appearance, odor and all otherexternal characteristics, the sodium yeast was ual in qualit to thenormal compre yeast containing the usual amount of potassium in every"way.

Having described my invention, what I claim as new and, desire to secureby Letters Patent, is t- 1,. The prooem of manufacturing yeast whichcomprises preparing a yeast nutrient solution, and propagating yeasttherein with aeration; the yeast nutrient solution containing sugarmaterial and inorganic salts adapted to supply all essential yeastnutrients with t e exoe tion of potassium, the potassium being rep acedby an equivalent amount of sodium.

2. The process of manufacturing. yeast which comprises preparing adilute yeast nutrient so ution, and propagating yeast therein withaeration; the nutrient solution containing sugar material and inorganicsalts comprisln ammonium compounds adapted to' nourish yeast and sodiumsalts in lieu of potassium salts.

3. The process of manufacturing yeast which comprises preparing a yeastnutrient solution, and propagating east therein with aeration; thenutrient so ution containing sugar material, ammonium salts ada ted tonourish yeast, sodium sulphate an magnesium sulphate.

4. The process of manufacturing yeast which comprises preparing a yeastnutrient solution, and propagating east therein with aeration; thenutrient solution containing sugar material, ammonium salts adapted tonourish yeast, sodium sulphate, magnesium hate, and a neutralizeradapted to neuize the mineral acids set free by the props. ati'ng yeast.

5. he process of manufacturing yeast which comprises preparing a yeastnutrient solution, and propagating east therein with aeration; thenutrient so ution containing about 100 parts spfiar material, about 4.5parts ammonium c phate,about 1.5 parts ammonium dihydro en phosphate,about 6.8 parts sodium sulp ate,' about 0.5 parts magnesium sulphate,about 7.0 parts chalk and about 5000 arts water.

6. In the art of manufacturing compressed bakers yeast from nutrientsolutions containing only sugar material and inorganic yeast nutrientsalts, the step which comprises substituting sodium eompounds forpotassium compounds by cultivation through many generations.

Intestimony whereof I have aiiixed my signature.

sul tr FRIEDRICH HAYDUCK.

' error afpeera in the printed specification rcquirin Certificate ofCorrection.

It is hereby certified that in Letter -Patent No. 1,449,104, rantedMarch 20, 1923; upon the application of Friedrich Hayduck, of Wilmer-sorf, Germany, for an improvement in Processes for the Manufacture ofCompressed Yeast, an

correction as follows: Pa e rd for read or; and that t e said LettersPatent shou d 1, line 03, for the we e same may conform to the record ofbe read with this correction therein that th the case in the PatentOflice.

Signed and sealed this 29th day of May, A. -D., 1923. r r [M] KARLFENNING, Acting 0mm of Patents.

